When examining the tissues in a particular site in a patient's body, it is common for the examiner to take tissue samples from the site for analysis. This is referred to as a biopsy. A number of different biopsy devices for taking the tissue samples are in use. Typically, these biopsy devices are used in conjunction with other devices. These other devices have a lumen through which the biopsy device passes.
Some of the biopsy devices take the form of a forceps design with opposing jaws. The jaws are attached to the distal end of an elongate tube, which can be flexible or rigid. The jaws are opened and closed by an actuating mechanism. The actuating mechanism is controlled by manipulating controls located at the proximal end of the elongate tube. The actuating mechanism moves proximally and distally within the lumen of the elongate tube. This causes the jaws to rotate about an axis to cut and hold the tissue sample.
Various designs have addressed the mechanism by which the jaws pivot, and by which the actuating mechanism is attached to the jaws or to other elements which cause the jaws to open and close. These design elements combine to affect the important functional elements of the biopsy device, such as the cost of manufacture and assembly, stability, durability, ease of cleaning and sterilizing, hazards to operating personnel when cleaning and sterilizing the device or removing tissue samples, overall length of the jaw mechanism which affects the radius in which it can be passed through the bent lumen of devices used in conjunction with it, and wear or damage to the lumen of devices used in conjunction with it.
Prior art pivot mechanisms incorporate a clevis and pin, in which the pin may be a separate pin or may be an integral part of one of the jaws. Examples of biopsy devices which incorporate a clevis and integral pin may be seen with reference to U.S. Pat. No. 5,535,754 to Doherty. Examples of biopsy devices which incorporate a clevis and separate pin may be seen with reference to U.S. Pat. No. 5,238,002 to Devlin et al.
The mechanisms by which the actuating mechanism is connected to the jaws or elements, and cause jaws to open and close may be seen in reference to U.S. Pat. No. 5,133,727 to Bales et. al., U.S. Pat. No. 5,228,451 to Bales et al., U.S. Pat. No. 5,439,478 to Palmer, U.S. Pat. No. 5,238,002 to Devlin et al, U.S. Pat. No. 5,535,754 to Doherty, U.S. Pat. No. 5,820,630 to Lind and U.S. Pat. No. 4,887,612 to Esser et al.
During an examination of tissues at a site within a patient's body, the operator will want to take many samples of tissues, so as to increase the probability of obtaining tissues representative of the medical condition. When using biopsy devices that obtain and store only a single tissue sample, the device must be removed from the body, the tissue sample removed, and the biopsy device re-introduced into the patients body. The site of interest must be relocated prior to obtaining another tissue sample. This increases the time of the entire examination. The increase in time affects the cost of the procedure and risk to the patient. When the biopsy device passes through the lumen of devices used in conjunction with it, wear or damage to the lumen can occur, proportional to the number of times the biopsy device passes through the lumen.
Various designs have addressed the mechanism by which multiple tissue samples may be obtained and stored prior to removing the biopsy device from the patient. In each case the tissue sample is moved along the storage element by compression of successive samples against it, which can damage delicate tissue samples.
Examples of designs in which the sample is obtained by a side-facing cutting device or cutting knife and storage tube may be seen with reference to U.S. Pat. No. 4,651,753 to Lifton, U.S. Pat. No. 5,601,585 to Banik et al., and U.S. Pat. No. 5,810,744 to Chu et al. Examples of designs in which the sample is obtained by a means which incorporates a needle and storage tube may be seen with reference to U.S. Pat. No. 5,823,971 to Robinson et al. Examples of designs in which the sample is obtained by a set of cutting jaws, a transfixing needle and storage tube may be seen with reference to U.S. Pat. No. 5,779,648 to Banik et al., U.S. Pat. No. 5,562,102 to Taylor et al. and U.S. Pat. No. 5,840,044 to Dossa et al.
These references do not disclose a device in which elements are engaged to transport the tissue sample in the storage element so as to avoid its transport by means of compression of successive samples against it, which can damage delicate tissue samples. Nor do these references disclose a device in which the elimination of the clevis and the incorporation of a pin integral to one of the jaws are found in combination, in which the attachment of the actuating mechanism to the jaws is such so as to eliminate exposure of the ends of the actuating mechanism, and in which a flexion element is incorporated to re-open the jaw assembly.